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  • Top File of PVS power Library

     
    %------------------------------------------------------------------------------
    % Generalized Power function (without ln/exp)
    %
    %     Author: David Lester, Manchester University & NIA
    %
    %     Version 1.0            19/08/08   Initial version (DRL)
    %
    % This library provides Roots, Powers and Generalized Logs
    %
    % The (achieved) aim is to avoid using all libraries except those in
    % the standard prelude. Hooks are provided so that the power function
    % along with root and log can be shown to be continuous (over
    % suitable domains), but no continuity libraries have been used to
    % construct this library, meaning that it is built directly onto the
    % standard SRI prelude.
    %
    % Features include:
    % 
    % By INCLUDING root, you can have statements like:
    %
    %   root(8,3) = 2
    %
    % By INCLUDING real_expt, you can have statements like:
    %
    %   8^(1/3) = 2
    %
    % BY INCLUDING log, you can have statements like:
    %
    %   log(2)(8) = 3 /* = ln(8)/ln(2) */
    %
    %------------------------------------------------------------------------------
    
    top: THEORY
    
    BEGIN
    
      IMPORTING rational_props_aux, % Extra properties for prelude
                exponentiation_aux, % Extra properties for prelude
                nn_root,            % nth-roots of nnreals 
                root,               % nth-roots of reals
                                    %  (includes negative reals, for odd n)
                nn_rational_expt,   % x^y (x:nnreal, y: nnrat) Note 0^0 = 1
                nnreal_expt,        % x^y (x,y: nnreal)
                real_expt,          % x^y (x:nnreal, y:real) provided y>=0 when 0^y
                nn_log,             % inverse of nnreal_expt
                log,                % inverse of real_expt
                real_fun_power,     % exponentiation of functions
    
                ln_exp_def          % linking log to ln and ^ to exp
    END top
    

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